hallo everybody
I happily sail formula 162, futura 144 and futura 122 with race sails from 12 to 7 m2 which are very nice to sails (freeride sailing) in a range of winds ranging from 10-12 knotrs to 25-30 knots
I am very interested in ultrasonic as I weight 100 kg and formula is a bit demanding in terms of athleticism
is anybody who can describe the hull shape of ultrasonic in comparison with the boards I already own and sail?
any comment is appreciated
marco faillla

I think the answer your looking for is pretty straight forward here. I do not own have a US147 but I have seen them in the flesh. I have used the much older iS150, but this was pretty different design from the US147 but had a similar target market, big light wind slalom performance for those that don't want or like freedride boards, yet less physical/technical than formula.

US147 Vs F162. US147 much much easier and far less physical c/w F162. The 162 has sharp rails etc, in contrast the US147 is more like slightly de-tunes iSonic.

The description on the SB site is probably spot on, so go with that info.

I guess that you could drop your 162 and 144 and replace them with the US147. You'll loose maybe 3 knots or so on the bottom end, and maybe a bit of control as the wind picks up. But I reckon that a US147 to F122 should be good

The 2013 UltraSonic 147 change with the fast rocker line of the iSonic light winds group and benefits too of all the iSonic tail design to reduce the wet surface as much as possible with out loosing anything.

Even at your weight you will get planning with your 12 approximatively at the same time for 2 reasons :
1 : The board is a lot physical demand to get on the plane due to the extra length
2 : Less wet surface in the tail who help a lot to get on the plane, important part is the width around the front foot straps to get on the plane.

Of course the Formula will go up wind better than the UltraSonic but except that the board will be easier everywhere and faster.